There are a variety of tablet computer accessory devices designed to hold a tablet computer hands-free (e.g., without the need for a user to hold the tablet computer with their hands or any other body part) and/or stationary in a variety of user situations. Of these existing devices, they can be divided into four broad categories.
Category A: This category represents devices that are generally intended to be used on a flat surface as a stand. They comprise, generally, a planar surface for contact with the flat surface and another surface projecting upward from the planar surface. Some devices in this category function as both covers and stands.
These aforementioned devices are used to prop-up a tablet computer for hands-free use. However, the devices in this category are limited in that they require a flat and stable surface for stability.
Category B: A second category of devices hold the tablet in an upright position, but without the need for a flat surface such as a table-top. In lieu of a flat surface, devices in this category are able to prop up tablets with the use of a body part of a user, such as the legs or lap of a user.
The devices in this category, unlike those in Category A, can be used without a flat and stable surface to rest the device on. They use various body parts of the user to maintain their stability. The limitation of the devices in this category is that the user must remain still to avoid movement of the device. When the body part that the device is resting on moves, so does the device, thus limiting the user's movement and ease of use.
Category C: The devices in this category are able to hold tablets in an upright position while the user is in a bed or chair, without having to rest it on the user's body part. This category shares some characteristics with those devices in both category A and B. Devices in this category have a piece that rests on an adjacent surface and a single arm to hold the tablet in place.
These devices allow tablets to be used while the user is in a bed or a chair, without having to rest the device on a body part, however the limitation of devices in this category is that while they allow tablets to be used in a bed or a chair, they still require an adjacent flat and stable surface for the piece of the device to rest on or be affixed to. As such, they are not useable in situations where an adjacent stable platform is not available. An additional limitation of this category of design is that due to the mount being suspended on a single arm/leg, there is a lack of stability when typing or otherwise using the touch-screen of the device being held; thus resulting in unwanted swaying or movement of the device.
Category D: This category addresses the limitations of all the previous categories in terms of using tablets in a bed or chair without either a flat resting surface or having to rest such devices on a body part. Instead, they depend on rigid arms resting on a surface to support tablets.
The devices in this category allow for a tablet computer to be used in a bed or a chair without the need to rest on a body part or have an additional flat or adjacent stable surface to rest the device on. However, the devices in Category D have several limitations.
First, the fixed plane configuration of the individual legs that support the device make them less than satisfactory, in terms of stability, for use on a bed or cushioned surface—especially one that may be exceptionally uneven on the surfaces where the legs rest. This results in a potential tilting of the viewing angle in the left-right axis that cannot be overcome, as the portion of the device that the tablet rests on is fixed to a 90 degree angle to the vertical plane of the supporting legs. If the legs are on uneven surfaces, then the left-right horizontal viewing axis will be tilted, resulting in a tilted viewing angle for the user.
A second limitation of category D designs are that they do not allow for a toward-the-face viewing angle that is less than 90 degrees. This prevents viewing a tablet device from a head-on direction while lying in a full supine position.
Attempts to overcome these issues have been unsuccessful. Some designs add a single-arm flexible neck which is attached to a central joining piece. However, the single-arm neck adds height to the whole assemblage and must be bent off center from the joining piece to place a tablet computer in a viewable position. This configuration gives the device a higher center of gravity, making it less stable and more top-heavy.
Other designs attach legs to the underside of a central joining piece, requiring the legs to make a 90° vertical turn upward into the body. This configuration uses more leg length than necessary for the function of the device. It also adds more extraneous height and bulk, making it clunky and giving it an awkward, less usable profile.
Further designs use gooseneck legs attached to the center body using male and female threaded ends. Given that the function of the gooseneck legs are made to be bendable into various shapes, the twisting and turning of the legs cause the threaded ends to easily loosen and twist inside of the central joining piece (i.e., become unscrewed), thereby reducing the devices functionality and usability.